In recent years, advantages of connecting a computer or a data processor to a network have been widely recognized, and the number and types of apparatuses connected to a network (described as network-connected apparatuses hereinafter) are increasing. In association with this tendency, network structure is becoming increasingly complicated, and now there is the need for management of network-connected apparatuses.
As a tool for management of information of network-connected apparatuses, there has been known an apparatus which collects device names or information for connection in a network in the online mode and provide the collected information to, for instance, a network manager. By using a tool of this type, a user can collect and manage network information without going to a place where the network-connected apparatuses are located. Also with a tool of this type, it is possible to collect information for network connection and provide, for instance, a tree-formed layered-display of the information for network connection on a display screen of a network managing apparatus, so that the user can edit the information to a state similar to an actual layout with a graphic tool by maintaining the network connection state as it is.
As a unit for collecting information for a position where an object at a remote site is present, there is known a system that uses the GPS (Global Positioning System) or the PHS (Personal Handy-Phone System). GPS is a system which receives electric waves transmitted from a plurality of communication satellites and determines the position of an object, namely a car or a ship moving with a receiver for GPS installed thereon from the delay time of each received electric waves. A system making use of the PHS receives electric waves transmitted from a plurality of base stations using a PHS terminal (a simple portable telephone terminal) and detects the position of the PHS terminal as a mobile station according to amplitude of the received signals.
The network information management tool based on the conventional technology as described above can detect a change in position, when the logical network connection structure namely the structure indicating only connection between network-connected apparatuses and not indicating actual location of the network-connected apparatuses is changed, but can not detect a change in the position, when actual location of the network-connected apparatuses are physically changed while maintaining the logical network connection structure as it is. Namely, with the conventional tools as described above, information on physical position of each network-connected apparatus is not collected as one type of network information from each apparatus, so that physical movement of network-connected apparatus is known only to a person who has actually moved the network-connected apparatus.
In a case of network management in a small organization in which all of network-connected apparatuses are completely put under control by a network manager, the network manager will know a change in the physical position of each network-connected apparatus and reflect the information to the management information. However, as a scale of a network becomes larger, it becomes difficult to accurately and immediately manage physical movement of all network-connected apparatuses. The reason is that, even if it is tried to divide a large-scale network into several small-scale networks, a time delay may be generated between actual movement of a network-connected apparatus and updating of the movement information or a destination of movement of the network-connected apparatus may be erroneously inputted so far as the network management is manually executed.
Also when the network structure is displayed as a tree-formed layered structure on a display screen, or when a user uses a graphic tool to edit or have layout information displayed with the network connection state unchanged, a time delay may be generated in updating the positional information or a user may input erroneous information.